Dental impression tray



Sept. 1, 1959 s GRE4ENMUN 2,901,825

DENTAL IMPRESSION TRAY Filed Nov. 8, 1957 2- Sheets-Sheet l v INVENTOR.LEO S. GREENMUN ATTORNEY P 1, 9 L. s. GREENMUN 2,901,825

DENTAL IMPRESSION TRAY Filed NOV. 8, 1957 2 Sheets-Sheet 2 INVENTOR. LEOS. GREENMUN AT TORN EY United States Patent 6 DENTAL IMPRESSION TRAY LeoS. Greenmun, Vero Beach, Fla.

Application November 8, 1957, Serial No. 695,463

7 Claims. (CI. 32-17) This invention relates to dental impression traysand is more particularly directed to impression trays for the productionof a lower denture constructed in accordance with my U.S. Patent No.,641,835.

In my aforesaid U.S. patent, I show and describe a flexible lowerdenture consisting of two substantially symmetrical parts abuttingtogether at their inner ends at the position between the two front teethwith. a leaf spring imbedded in the plastic material forming the dentureto permit the compressing of the rear or outer ends for positioning thedenture in a persons mouth or for removing same. As explained in detail,in my patent this construction permits the denture to fit against theundercut surfaces of the mylohyroid ridges and thereby fit snugly andproperly in a persons mouth and also to compensate for displacement ofthe supporting tissues resulting from the flexing of the mandible when aperson is biting and chewing.

To achieve an accurate impression of the lower jaw for the purpose offitting a lower artificial denture which makes use of the mylohyroidridges to anchor the denture thereto, a special impression tray must beused. Since the lower inside surfaces curve under the mylohyroid ridges,it is impossible to remove the impression and tray in a single piece forthe reason that the impression made is larger at the bottom and insideedges thereof than is the opening through which the impression and traymust be removed.

I, therefore, conceived of the present tray which consists of two partsabutting at their inner portions with a pair of handles mounted on thetray and a spring means for yieldingly urging the inner portions of thetray in abutting relation. The handles permit the handling of the trayin placing the tray in ones mouth and in removing same, and also thecompressing or collapsing of the outer portions of the tray in thedirection toward each other so as to obtain an accurate impression ofthe undercut surfaces of the mylohyroid ridges.

Now therefore, a principal object of the present invention is to providean impression tray for obtaining a true impression of ones lower gumstructure for a persons lower artificial denture especially of theundercut surfaces of the mylohyroid ridges in order to produce a denturethat will fit properly thereon.

A further object of the present invention is to provide an impressiontray which is cut or split at approximately its center position, with aspring mounted on the tray yieldingly urging the two parts of the trayin abutting relation, a pair of handles for collapsing or compressingthe outer ends of the tray in a direction toward each other and anadjustment bolt for positioning the two parts of the impression tray atany desired relative position.

A still further object of the present invention is to provide a handledevice for impression trays formed of a metallic rod and having a springlike mid-portion yieldingly urging the handles in a direction away fromeach other.

Patented Sept. 1, 1959 A still further object of the present inventionis to provide a handle device described as above which device is readilymountable on a metallic or plastic impression tray.

With these and other objects in view, the invention will be bestunderstood from a consideration of the following detailed descriptiontaken in connection with the accompanying drawings forming a part ofthis specification, with the understanding, however, that the inventionis not confined to any strict conformity with the showing of thedrawings but may be changed or modified so long as such changes ormodifications mark no material departure from the salient features ofthe invention as expressed in the appended claims.

In the drawings:

Figure 1 is a bottom plan view of a dental impression tray embodying myinvention.

Figure 2 is a top plan view thereof.

Figure 3 is a side elevational view thereof.

Figure 4 is a view similar to Figure 1 showing the tray in itscompressed or collapsed condition.

Figure 5 is a top plan of an impression tray having a modifiedconstruction.

Figures 6 and 7 are bottom plan and side elevational views respectively.

Figure 8 is a top plan View of a further modified structure of myimpression tray.

Figures 9 and 10 are bottom plan and side elevational views respectivelythereof.

Figure 11 is a cross sectional view taken along the line 1111 of Figure8.

Figure 12 is a perspective view of the spring handle device as shownprior to its being secured to the impression tray.

Figure 13 is a further modified construction of my dental impressiontray having handles and a spring member as separate members aflixedthereon.

Referring to the drawings wherein like numerals are used to designatesimilar parts throughout the several views and in particular to Figures1 to 4 inclusive, the numeral 10 refers to my dental impression traygeneral ly which is U-shaped and arcuate to form a trough along the fulllength as are the conventional impression trays; however, the tray 10 isconstructed of two leg portions 11 and 12 abutting at their inner endportion as at 13. The inner end portions of the leg portions 11 and 12are joined together by a leaf spring member 14 which yieldingly urgesthe leg portions 11 and 12 into abutting relation. The inner end portionof the leg portion 12 is provided with a flange 15 which overlaps thelower surface of the inner end portion of the leg portion 11 at allpositions of the leg portions 11 and 12.

Means are provided for swinging the leg portions 11 and 12 comprisinghandles 17 and 18 secured at one end to the leg portions 11 and 12respectively and extending rearwardly terminating in flared portions 19and 20 adapted to fit in a persons fingers for operation thereof. Thehandle 17 is slotted as at 21 for receiving the handle 18 and whoseinner end operates as a stop to prevent the handles 17 and 18 fromswinging beyond a certain desired position.

Extending from the handle 18 is a tab support 22 on which is secured asby welding a threaded support 23 for an adjustment bolt 24. A knurledknob or head 25 is secured at one end of the adjustment bolt 24 whilethe other end engages a tab 26 mounted on the handle 17.

In using the impression tray 10, as in using the conventional tray, thetray is first prepared for an impression and the dentist grasps thehandles 19 and 20 between his thumb and forefinger. He exerts a forcethereon to cause the handles 19 and 20 to swing toward each other andthe leg portions 11 and 12 will pivot about the spring 2, SM 32b 14 sothat the outer ends of the tray are compressed or collapsed toward eachother thereby making the tray 10 smaller in size. In this condition, thetray 10 is inserted ina-person smouth and placed in position on thelower--gums.- The force of thefingerson the handles 19 and 20 isreleased slightly topermit the outer edges of the tray 10to engage thesides of the gums with-only sufiicient pressure to obtain. thedesiredimpression Then the adjustment: bolt 24- is threaded-until the end ofthe bolt 24 engagesthe tab; 26. 'I'hen the"handles 19'and 20 arereleased to efiect the impressions When the impression has been made,thedentist again-grasps the handles19 and '20 with his thumband-forefinger, forces the handles 19 and-20 together to-their extremeopened of lower jaws of different sizeswith accuracy of the impressionproduced.

However, where it is desired to have-a plurality of impressiontrays ofvarious sizes so thatthe dentist making the impression may select thesize of tray most suitable for the person-whose'lower gums arebeingfittedfor an artificial denture, I have provided an'impression traypreferably made ofmetal shown by Figures 5-7 inclusive. Just as the tray10, the tray 30 consists ofa-pair of leg portions 31 and 32 whose innerends are in-abutting relation as at 33. At the position 33 at which theleg portions 31 and' 32abut, the latter are provided with a flange 34 onthe extreme ends thereofl With the flanges 34 in contact relation witheach other, ahandle 35 issecured as by riveting 'as shown or by anyother desired manner to the legportions-31 and 32s The handle 35 isconstructed from a lengthof metallic rod, flattened and bent into anarcuate shape as at 36 to form a spring and returned at an obliqueangleas at 37, 37 to permit the riveting of the handle 35* to-the legportions 31 and:32. The handle portions are stepped as at 39; crosseachother and extend outwardly to form portions 38 and 38 for grippingby a dentist to-manipulate the impression-tray30. Prior tomounting-the-handle 35 on the tray 30, the handle portions 38'arecompressed slightly to place the spring" portion 36 under tension. Thenthe'portions37, 37 are secured to the leg portions 31, 32 whose flanges34, 34 are in-contact relation with each other. The tension in-thespring portion 36 now maintains the legportions 31, 32 in-firmabuttingrelation so thatwhen the handles 38,- 38 are relieved of any forces, theleg portions 31, 32 will return to their abutting relation.

There are dentists who use the impression tray 10 shown by Figuresl-4inclusive to make a smaller and better fitting tray 40 of plastic whichis used only once and then discarded' (Figs. 8-11 inc.) Upon producingthe plamic-tray 40, which is in one piece originally, an extremelyinexpensive handle 41 is mounted on the tray by cgmenting v the handle41 thereon with a plastic material as indicated at 42. The plastic tray40 is then sawed in two symmetrical portions 43 and 44 as' at 45 at theexact. center portion of the tray 40, which center was first drilled asat 46 for convenience. The handle 41 is substantially identical inconstruction with the handle 35 consisting of a single length ofmetallic rodbent as at. 47 for forming the spring portion of thehandle41. The adjacent portions 48, 48 of the handle 41 are bent and extend atan oblique angle to each other, steppedupwardly as at 49 and cross eachother to form handle a plastic tray 40 (see Figure 8) or on a metallictray 30 (see Figure 5) and is therefore provided with bores 51 in theevent it is desired to rivet the handle 41 to the impression tray. It isto be noted that the handle 41 is inexpensive in cost and can bediscarded after a single use along with the impression tray to which itis afiixed. The handle 41 accomplishes its function of maintaining theleg portions 43 and"44" of the tray 40 in abutting relation, permits theinward flexing of the'leg portions 43 and 44 when the handle ends 50, 50are pressed together and flexes the leg portions 43, 44 outwardly intocontact relation at their inner ends when the pressure on the handleends 50, 50 is released.

Another inexpensive manner of constructing a dental impression trayembodying my invention is shown by Figure 13. There, a tray which isformed in two portions 55, 55 as are the above described trays, isprovided with a spring 56 whose ends are embedded in cement, plastic orthe like atiixingthe'spring 56 to the portions 55, 55. The spring 56'yieldingly urges the abutting inner end portions into firm' contactrelation. Handles 57, 57 which are crossed are constructed ofsubstantially straight metallic rods with their inner ends imbeddedin'the cement in the same manner as the spring 56. Now when pressure isplaced on the outer ends of the handles 57, 57 the outer end' portions55, 55 of the'tray will collapse, swinging ina direction towardeach-other and when released the inner end portions will return to'theirabutting relation asthe outer ends 55, 55 ofthe tray will swing awayfrom each other.

What I claim as new is:

1. An impression tray comprising a pair of arcuate-leg portions forminga substantially U-shaped member, said leg portions having their innerendsin substantially contact relationship, spring means mounted on saidleg portions and yieldingly urging said inner'ends' into contactrelation and handle means mounted on said' leg portions for collapsingsaid leg portions, swinging said inner ends about said spring means as ahinge in a-=direction away 'from each other and the other ends'in-adirection toward each other.

2. An impression tray comprising a pair of arcuate leg portions havingaligned troughs forming a' substantially U-shaped member, said legportions having their inner ends in contact relation, springmeansextending over the puncture of said inner ends, means securing saidspring means to each of said leg portions whereby said leg portions areyieldingly urged into contact'relation at said inner ends, a handlehaving one end secured to each of said inner ends and the'other'endextending'ina di rection away fromsaid leg portions whereby uponexerting a force on said other ends of said handles said leg portionsare collapsed, said inner ends swinging'in a direction away from'eachother and the other ends swinging in a direction toward each other.

3. The structure as recited by claim 2 in combination with stop meansmounted on said other ends of said-handles for limiting theoutwardswinging movementof said inner ends and adjustable means forlimiting the inwardswinging movement of said inner ends.

4. An impressiontray comprising a pair of arcuate leg portions having.aligned troughs to form a substantially U-shaped member, said legportions having inner ends in substantially overlapping and contactrelation, a spring member extending over said overlapping portions andhaving ends secured to said leg portions, a handle having one endsecured to each of said legportions and the other end extendingoutwardly, said handles crossing each other intermediate their ends, oneof said handles having a slot receiving said other handle for limitingthe relative outward swingingmovement of said handles, an adjust mentbolt threadedly mounted on said one of said handles, and a tab mountedon said other of said handles adapted to abut against said adjustmentbolt for limitin".

5 the inward swinging movement of said areuate leg portions.

5. The structure as recited by claim 1 wherein said spring means andsaid handle means are constructed of an elongated metallic rod.

6. An article of manufacture for impression trays formed from anelongated metallic rod comprising an arcuate mid portion, said arcuateportion having leg portions and handle portions each having one endportion extending from said leg portions, said handle portions crossingeach other intermediate said end portions whereby upon forcing saidhandles together said leg portions are swung in a direction toward eachother.

7. An article of manufacture for impression trays formed from anelongated metallic rod comprising an arcuate mid portion flattened toprovide spring tension,- said arcuate portion having outwardly extendingleg portions, and a pair of handles, each handle having one end portionflattened and extending from said leg portions, said flattened portionsof said handles lying in a plane intersecting said arcuate portion toprovide rigidity to said handles, stepped up portions extending fromsaid flattened handle portions, said stepped up portions cross ing eachother whereby upon the forcing of said handles together said legportions of said arcuate portion swing in a direction toward each other.

References Cited in the file of this patent FOREIGN PATENTS 545,545France July 26, 1922

